Gas prices continue to increase, and many analysts believe prices will once again top $4 per gallon sometime this year. Many drivers are looking to save money at the pump, but not everyone has the cash to go buy a high-MPG hybrid or electric vehicle. Fortunately, there are some types of auto maintenance that drivers can look into in order to improve their fuel economy.

Perhaps the most important part of your vehicle when it comes to fuel efficiency is the oxygen sensor. Many drivers may not even know that their vehicle contains an oxygen sensor, or why it's important. However, this device is critical in determining the appropriate fuel mixture for your vehicle. Engines ultimately run on a combination of oxygen and gas, and the sensor's job is to detect how much air is in the engine. This in turn tells the car how much fuel to allot in order to keep the car running.

Thus, it's easy to see how fuel economy can quickly become troublesome if the oxygen sensor is faulty or broken. These parts wear out over time, so if you have an older vehicle that's never had its oxygen sensor replaced, you might want to consider getting a new one as a bit of preventative maintenance. If the sensor was broken or not working correctly and you choose to replace it, it could improve your MPGs by up to 40 percent. It's especially important to take a look at your oxygen sensor if you've noticed that you seem to be hitting the gas station more often than you used to.

Oil is another important aspect of the car when it comes to auto maintenance. While an oil change would have decidedly minor effects on fuel economy, one area that drivers should pay close attention to is the grade of motor oil that they're using. Every automaker recommends a certain grade for their vehicle, and it's with this type of oil that all fuel economy tests are done. Using a different type of motor oil may lower your MPGs, so it's best to stick with the manufacturer's recommendation. Some drivers like to use different grades depending on where they live, but these owners should know that they could be lowering their fuel economy by doing so.

A common misnomer when it comes to auto maintenance and fuel economy is that the air filter will improve MPGs. Recent studies have shown that in modern fuel-injected cars, this is no longer the case. Vehicles that still use carburetors could see a major improvement from replacing a clogged air filter, however. On modern vehicles, cleaning the air filter is still a good idea. Although it won't directly help your MPGs, it will improve your acceleration time, meaning you won't have to press on the pedal quite so much - which in turn will allow you to use less gas when getting up to speed.

Besides popping the hood, there are a few more things that drivers can consider to squeeze MPGs out of their vehicle. Driving with a roof rack will hurt a car's aerodynamics, which in turn lowers the fuel economy, so it's best to uninstall this feature if you're not using it. Weight is incredibly important when it comes to fuel economy, so unloading the car of junk and items can also help.